Nonaqueous electrolyte secondary batteries are widely used as power supplies for driving portable devices such as cellular phones, smart phones, and notebook PCs because of their high energy density and high capacity. Recently, there has been a need for further improvements in the cycle characteristics of nonaqueous electrolyte secondary batteries.
Electrode plates used in nonaqueous electrolyte secondary batteries are manufactured by applying to a core an electrode active material slurry containing an electrode active material, a binder, and a solvent, drying the resulting coating, and pressing the coated core. This method is advantageous in terms of productivity and discharge characteristics.
The use of an excessive amount of binder, which does not directly contribute to charge and discharge, decreases the discharge capacity. The use of an insufficient amount of binder decreases the peeling strength of the electrode active material layer and thus results in the electrode active material easily peeling off the core.
Example techniques related to binders for nonaqueous electrolyte secondary batteries are disclosed in PTLs 1 to 5 below.